Apparatus for horizontal, continuous metal casting



Dec. 13, 1966 A. J. WERTLI 3,290,734

APPARATUS FOR HORIZONTAL, CONTINUOUS METAL CASTING Filed May 22. 1964 jrryemon' 74mm J. Mar

United States Patent 3,290,734 APPARATUS FOR HORIZONTAL, CON- TINUOUS METAL CASTING Alfred J. Wertli, 15 Poststrasse, Winterthur, Switzerland Filed May 22, 1964, Ser. No. 369,562 Claims priority, applicagionl S/vgtzerland, May 25, 1963,

4 3 Claims. 61. 22-s7.2

The present invention relates to a method and an apparatus for horizontal, continuous casting of metals.

It is conventional to pull the cast metal from the mold intermittently or continuously when casting metal horizontally and continuously. With this procedure the surface and also the texture of the cast metalis not always homogenous because the surface of the metal does not always evenly separate from the mold. It also happens that the metal breaks. 1

It is an object of the present invention to provide a method and apparatus for horizontal, continuous metal casting which-avoids the shortcomings of conventional methods and apparatus and affords even separation of the metal from the mold, assuring a homogeneous structure of the cast metal free of pores. The metal obtained by the method and apparatus according to the invention is mechanically strong and has a great tensile strength at maximal elongation.

In the method according to the invention the metal is pulled from a stationary mold through a predetermined distance whereafter it is moved somewhat toward the mold and thereafter again pulled away from the mold and so on for generally moving the metal away from the mold. The distance through which the metal is intermittently advanced is greater than the distance through which the metal is subsequently moved back toward the mold. In the method according to the invention the metal is advanced in pilgrim step fashion, whereby the metal travels a short distance in opposite direction after each forward movement. In this way the periods of time during which the metal is stationary in the mold are shorter than in conventional processes wherein the metal is intermittently advanced so that adherence of the metal to the wall of the mold is reduced and the metal is more evenly separated from the wall of the mold than in conventional processes. Because of the return movement of the metal the liquid metal at the inlet of the mold is additionally moved whereby premature solidification at the inlet of the mold is avoided and the liquid metal flows into the mold and follows the solid metal without disturbance when the metal is advanced. Due to the repeated movement of somewhat cooled metal into a hotter zone of the mold, the structure of the metal is improved throughout the length of the metal. The method according to the invention assures undisturbed operation of the casting process and results in a good quality product which has no surface cracks, liquations or segregations.

The apparatus for performing the method according to the invention includes a power accumulator operatively connected to the metal which accumulator absorbs and accumulates power when the metal is pulled away from the mold and which releases power for moving the metal toward the mold during the periods of time when the pulling-away apparatus is inactive.

The novel features which are considered characteristic of the invention are set forth with particularly in the appended claims. The invention itself, however, and additional objects and advantages thereof will best be under stood from the following description of an embodiment thereof when read in connection with the accompanying drawing, the one figure of which is a diagrammatic partsectional illustration of an arrangement according to the invention.

3,290,734 Patented Dec. 13,- 1966 Referring more particularly to the drawing, numeral 1 designates a mold surrounded by a cooler 2 and connected to a furnace 3 containing metal to be cast. The cast metal 4 is pulled out of the mold 1 by a conventional pulling apparatus 5 of which only two clamp jaws 15 are shown which are, for example, hydraulically pressed against the metal 4 as indicated by arrows. The finished product rests on a roll-table 7. A device 8 is located between the pulling device 5 and the mold 1 for intermittently moving the metal 4 toward the mold. The metal is pressed between two jaws 9 which are guided to move in vertical direction by a frame 10. The pressure exerted by the jaws 9 on the metal 4 is adjustable by manipulating screws 11. In the illustrated position the clamp jaws 9 abut against abutments 12 which may be, for example, in the form of screws and adjustable. At the opposite side of the clamp jaws 9 a spring 13 is provided which is interposed between the jaws 9 and a stationary plate 16. The latter supports adjustable abutments 14 which may be, for example, in the form of screws.

7 The process according to the invention is performed as follows:

The jaws 15 of the pulling device 5 are pressed against the metal 4 which is then pulled in the direction of the arrow 6. The jaws 9 and the frame 10 of the device 8 are taken along by the metal until the jaws 9 abut against the abutments 14. The path travelled by the jaws 9 is shorter than the distance the metal is pulled by the device 5 so that the metal 4 slides on the jaws 9 after the jaws have reached the abutments 14. When the pulling device 5 has completed its predetermined travel the jaws 15 are opened and the metal 4 is moved in the direction of the arrow 17, Le. toward the mold 1, by the force of the spring 13 acting on the jaws 9. This reverse movement continues until the jaws 9 abut against the abutments 12. The power accumulator formed by the spring 13 which has been charged pull the latter in the direction of the arrow 6. The dis- I tance through which the metal 4 travels in the direction of the arrow 6 and the extent of the subsequent reverse movement of the metal in the direction of the arrow 17 depend on the type of the cast matter and also on its cross section. Both movements can be varied. The extent of the reverse movement in the direction of the arrow 17 can be adjusted by manipulating the abutments 12 and 14. of the device 8. The type of the cast material and its cross section also influence the time between the completion of the reverse movement in the direction of the arrow 17 and the beginning of the advance movement in the direc tion of the arrow 6. This time may be very short when casting certain materials so that an oscillating movement of the cast metal and also of the melt is produced. The reverse movement in the direction of the arrow 17 allows the solidified casting to scrape any metal particles adhering to the wall of the mold so that the metal subsequently emerging from the mold has a smooth surface. The cast metal has a fine and homogenous structure which is free of pores whereby the mechanical strength qualities of the metal are improved and a great tensile strength at maximal possible elongation is obtained.

It is possible to provide a plurality of molds 1 close to each other and to construct the pulling device 5 and the device 8 for receiving a plurality of metal strips so that a plurality of strips can be produced simultaneously with the process according to the invention.

metal:

a mold for continuously receiving molten metal and releasing solid metal,

intermittently active means connectible to the solid metal for intermittently advancing the metal away from said mold,

clamp means for frictionally engaging the solid metal for movement therewith in a first direction,

abutment means for limiting the extent of movement of said clamp means to permit sliding of the metal relative to said clamp means during movement of the metal in said first direction, and

power accumulating means engaged between said clam-p means and said abutment means for absorbing power during movement of said clamp means in said first direction, said power accumulating means releasing power to return the metal toward said mold when said intermittently active means is inactive whereby the metal is moved toward said mold a distance less than the amount of intermittent movement in said first direction to permanently withdraw continuing lengths of metal from said mold,

2. In an apparatus as defined in claim 1 said power accumulating means including a spring, said spring being compressed-upon movement of said clamp means in said first direction and expanded upon movement of said clamp means toward said mold.

3. In an apparatus for horizontal, continuous casting of metal a mold for continuously receiving molten metal and releasing solid metal,

intermittently active means connectible to the solid metal for intermittentlyadvancing the metal away from said mold,

clamp means for clamping the solid metal,

abutment means engageable by said clamp means for limiting the extent of movement of said clamp means to permit sliding of the metal through said clamp means for affording advancement of the metal by said intermittently active means through a greater distance than the extent of movement limited by said abutment means, and

resilient means engaged by said clamp means and compressed when the metal is advanced by said advancing means, said resilient means expanding and moving said clamp means and metal clamped thereby toward said moldwhen said intermittently active means is inactive.

References Cited by the Examiner UNITED STATES PATENTS 2,815,551 12/1957 Hessenberg et al. 22-200 X 3,025,579 3/ 1962 Littlewood 2257.2

FOREIGN PATENTS 881,454 3/ 1958 Great Britain.

I. SPENCER OVERHOLSER, Primary Examiner.

o R. S. ANNEAR, Assistant Examiner. 

1. IN AN APPARATUS FOR HORIZONTAL, CONTINUOUS CASTING OF METAL: A MOLD FOR CONTINUOUSLY RECEIVING MOLTEN METAL AND RELEASING SOLID METAL, INTERMITTENTLY ACTIVE MEANS CONNECTIBLE TO THE SOLID METAL FOR INTERMITTENTLY ADVANCING THE METAL AWAY FROM SAID MOLD, CLAMP MEANS FOR FRICTIONALLY ENGAGING THE SOLID METAL FOR MOVEMENT THEREWITH IN A FIRST DIRECTION, ABUTMENT MEANS FOR LIMITING THE EXTENT OF MOVEMENT OF SAID CLAMP MEANS TO PERMIT SLIDING OF THE METAL RELATIVE TO SAID CLAMP MEANS DURING MOVEMENT OF THE METAL IN SAID FIRST DIRECTON, AND POWEER ACCUMLATING MEANS ENGAGED BETWEEN SAID CLAMP MEANS AND SAID ABUTMENT MEANS FOR ABSORBING POWER DURING MOVEMENT OF SAID CLAMP MEANS IN SAID FIRST DIRECTION, SAID POWER ACCUMULATING MEANS RELEASING POWER TO RETURN THE METAL TOWARD SAID MOLD WHEN SAID INTERMITTENTLY ACTIVE MEANS IS INACTIVE WHEREBY THE METAL IS MOVED TOWARD SAID MOLD A DISTANCE LESS THAN THE AMOUNT OF INTERMITTENT MOVEMENT IN SAID FIRST DIRECTION TO PERMANENTLY WITHDRAW CONTINUING LENGTHS OF METAL FROM SAID MOLD. 